Wood chipper



H. w. WEXELL 3,069,101

WOOD CHIPPER Dec. 18, 1962 4 Sheets-Sheet 1 Filed Dec. 4, 1959 Dec. 18, 1962 H. w. WEXELL 3,069,101

WOOD CHIPPER Filed Dec. 4, 1959 4 SheetsSheet 2 Fig. 2

Dec. 18, 1962 Filed Dec. 4, 1959 H. w. WEXELL 3,069,101

woon CHIPPER 4 Sheets-Sheet 4 INVENTOR HARRY M. WEXELL ATTORNEYIS its ime

s earer Patented Dec. 18, 1962 3,069,1ti1 WGUD C'HHPPER Harry W. Wexeil, Soderharnn, Sweden, assignor to Sederharnu Verltstader AR, Soderhamn, Sweden Filed Dec. 4, 1959, Ser. No. 857,359 Claims priority, application .dweden Dec. 5, 1958 6 (Ilaims. (Cl. Mil-92) The present invention relates broadly to the art of Wood conversion, and is particularly directed to certain improvements in machines for producing wood chips.

The invention specifically relates to certain improvements in a wood chipper and a system for treating wood to produce chips of a desired size.

Many forms of wood chipping machines exist in the prior art which treat logs, slabs or the like by subjecting the ends thereof to the action of rotatable chipper discs carrying on one face a plurality of cutter knives.

In some machines, the logs are fed through a chute or inlet spout, which has its axis inclined downwardly and at an angle to a disc that rotates on a horizontal axis so that the logs can be fed to the chipper disc by gravity, and the cutter knives will cut bias slabs from the log which will disintegrate into chips. An arrangement of this character givesrise to certain problems in connection with the feeding of .the logs to the chipper in that they must be fed from a higher level than the chipper, and. consequently, the chipping system occupies a substantial amount of space in the vertical direction. 4

Other machines exist in which a feed means is provided that lies in a horizontal plane and extends at an acute angle toward the cutter disc. While this type machine will minimize space as regards an overall system, it has been observed that neither of the aforementioned chipping machines lend themselves to a system and an arrangement for chipping wood pieces to a desired size that is not only economical to construct, but is also one that could be termed of universal application.

Accordingly, the present invention has for one object to provide a system for producing chips which includes means for feeding logs to be chipped to a cutter disc supported for rotation on a horizontal axis, a housing surrounding said disc, means for withdrawing the material chipped from the end of a fed log from the housing, and for conveying the same to an initial separating zone, means for separating conveying air and some fine wood particles from the chipped material and for directing such chipped material to a further separating zone, means at said further separating zone for screening the chipped material to size including the elimination and return of oversize chips to the chipper so that they can be rechipped and conveyed back to the second separating zone.

It is a further object of the invention to provide a horizontal chipper construction including a chipper disc mounted for rotation on a horizontal axis, a housing surrounding said disc, a first infeed spout having its axis disposed horizontally and having an outlet end communicating with the housing at an acute angle to the face of the disc for receiving logs to be chipped, and a second infeed spout communicating with the housing at an angle to the horizontal for receiving material to be rechipped.

Further and more specific objects will be apparent from the following description taken in connection with the accompanying drawings in which:

FIGURE 1 is an elevational view from the infeed side of the chipper constructed in accordance with the invention with part of the housing broken away,

FIGURE 2 is a view partly in side elevation and partly in section along line 22 of FIGURE 1,

FIGURE 3 is a fragmentary cross-sectional view taken along line 22 of FIGURE 1, but on an enlarged scale and illustrating the outlet end of a downwardly inclined feed spout and the adjacent disc and housing portions,

FIGURE 4 is an enlarged scale fragmentary crosssectional view taken along line 4-4 of FIGURE 2,

FIGURE 5 is a view illustrating the chipping system of this invention,

The chipping system of the present invention includes the chipping machine, the stationary housing it? of which is suitably supported and carries bearings 12 for a horizontal shaft 14 to which is connected a cutter disc 16. The cutter disc is provided with slots 18 through the same with respect to which are mounted cutter knives 20. The active edges of the cutter knives are preferably positioned to extend at an axis toward a radius of the disc, as shown in FiGURE 1. The knives are mounted on a wear plate 24 which is secured to the disc and is likewise slotted to provide a knife holding recess. Bolt means 222 secure the knives to the wear plate and'cutter disc and shims can be inserted between the undersurface of each knife and the adjacent surface of the cutter disc to adjust the position of the cutting edge of each knife with respect to, the stationary knives or anvils discussed hereinafter. t The rear face of the cutter disc is provided with a plurality of fan blades, not shown. The cutter disc is surrounded by the housing 10 and an upper cover means including two parts 26 and 23. These parts are respectively hinged to the housing It) by hinge means 3?. and they are likewise hinged to one another. by a hinge means 30; This relationship perm-its various manipulations of the covers 26 and 23 relative to the housing for the purpose of providing access to the cutter disc. An upwardly extending outlet conduit 34 is connected to the cover past 26 so that under the action of the fan blades, not shown, the chips can be forced out of the housing.

Connected to the front of the housing it} is a horizontal infeed spout or chute 36. This chute extends horizontally below shaft 14 from right to left as viewed in FIGURE 1, is open toward the disc in, and includes an outer wall forming an acute angle with the plane of rotation of the cutter disc. This outer Wall is defined by sheet metal strip 38 having a separate extension 4% that can be removed for purposes of inspection. This separate section or cover 4d extends to a stationary knife or anvil 42, FIGURE 4, which is secured by screws 44 to an adjustable block dd that in turn rests on a metal block 61 secured by bolt and nut means 62 to the housing 10. An adjusting screw 63 permits adjustment of the block '60 and thus the anvil 42 relative to the plane of rotation of the cutter knives 20 and the outlet end of the cover 46 and thus the outlet end of the feed spout 36. The edge 46 of the anvil or stationary knife 42 is disposed in a plane transverse to the axis of the rotation and immediately adjacent the edges of the cutter knives 20. FIGURE 4 indicates that this edge 46 is vertical and the disc 16 is shown at the position when one of the knives 20 is passing the edge 46 at a time when the knife edge is substantially parallel to the edge 46. The logs to be chipped are fed to the knives while bearing against the plate 38 of the feed spout, and the cover 40 thereof, so that-the action of the cutter knives cut slabs at an inclined angle having a thickness corresponding to the desired length of the chips, which may be between 20 and 30 millimeters or between of an inch or 1% inches in length, depending upon the adjustments of the respective knives 2i} and 42.

In accordance with the invention, the machine is provided with a second feed chute or spout 48 positioned above spout 36 and on the same side of shaft 14 as the inlet end of spout 36, see HGURE 1. Spout or chute 43 is inclined downwardly toward the face of the cutter disc, and the stand it supports a stationary knife or anvil 50,

FIGURE 3, the edge 52 of which is horizontal and extends at right angles to the vertical plane containing the axis of shaft 14. The bottom edge of chute 48 extends generally parallel to the anvil St), the active edge 52 of which is substantially parallel with the cutting edges 46 of the rota-table knives 20 when the latter pass the anvil So. If desired, however, this edge 52 may be disposed at an angle relative to the edges 46 when they are in the horizontal position and are passing the anvil 50. The bottom of the chute 48 is provided through a portion of its length with a plurality of inverted V-shaped guide ribs or projections 54, FIGURES l and 2, which are parallel to one another and parallel to the side walls of the chute. In the embodiment illustrated, these ribs or projections are provided by wedge shaped wells formed in a separate chute part 56 that constitutes a prolongation of the chute 48. This chute part 56 can be adjusted axially of the chute part 43 so as to make the overall length of the second infeed chute adjustable to accommodate the position of the outlet end of the conveying means discussed hereinafter. The shape and disposition of the guide ribs 54- is such that rather long pieces to be rechipped or trim ends from the mill in their passage along the bottom of the chute 48 will assume a postion so that they feed to the disc longitudinally.

FIGURE 5 illustrates the chipping system of the present invention, the advantages of which are believed readily apparent. The system or installation diagrammatically illustrated in this figure includes the chipper denoted generally at C of the structure shown in FIGURES 1 to 4. A suitable motor M through a belt drive and transmission D drives the shaft 14 for the chipper. Slabs, edgings or logs are fed by infeed conveyor I to feed spout 36 from which the resultant chips are delivered via the vertical conduit V to the cyclone separator CS. The chipped material is deposited from the cyclone separator into a chip screen SC. This chip screen includes a feed trough which receives the chip material from the cyclone and delivers it to the top bed or tray of the screen. The screen includes a suitable frame, not shown, which supports a motor drive for a vertical shaft which at the lower end carries an oifset arm connected to a weight. Below the weight is another offset arm panallel to the first that is connected to a bearing mount carried on an X-shaped cross frame that in turn is connected to the corners of the chip screen. This X-shape cross frame and the chip screen are suspended by cables extending upwardly from the corners of the chip screen to a stationary mount. When the vertical shaft is driven, the drive from the weight to the chip screen causes any point on the chip screen to perform a circular movement about a circle of about approximately 4" in diameter, in one suitable installation. The details of the chip screen are not shown in the drawing since other chip screens known in the art could be employed provided they incorporate the proper separation aspects. The upper tray or screen in the chip screen device has openings therein which reject chipped material that is termed oversize. This material is delivered by gravity through the spout SP to a return trough or conveyor RC which delivers the oversized chip material to the spout 48 of the chipper so that this oversized material can be rechipped. The chips of the proper size are taken off the delivery spout DP to a chip conveyor CC while fines and sawdust are delivered to a sawdust conveyor SD. In addition to the chipping installation treating the logs or the oversized chips to be rechipped, trim ends from the lumber mill are delivered by trim conveyor TC to the spout 48. The trough 48 includes the raised ribs or guides 54 for turning oversized pieces and trim ends lengthwise in their passage to the outlet end of spout 48.

It is believed clear that the invention provides a wood chipping installation including the combination with a chipping machine having a chipper disc mounted for rotation on a horizontal axis of a first infeed spout having an outlet end for delivering wood to be chipped to the chipper disc, a conveyor for feeding such wood to the spout, means for conveying chipped material away from the chipping machine and for delivering such chipped material to a separating zone, at said zone a screening device for segregating chip material into at least proper size chips and oversize chipped material, a second infeed spout having an outlet end communicating with the chipping disc, a means for conveying oversized chipped material from the screening device to said second spout for rechipping such material and return to said screening device and means for conveying proper size chips away from said screening device. The installation further includes additional conveying means for conveying short wood pieces to said second spout. The first spout is disposed horizontally and has its inlet end located below and to one side of the axis of the chipping disc and the second spout is inclined downwardly toward the disc, located above the first spout and has its inlet end above the axis of the disc. Means are provided in the bottom of the second spout for guiding material to be rechipped, or short wood pieces to insure their feeding longitudinally of their axes and which guide means consists of ribs having a wedge-shaped cross section. One feature of the invention provides the second spout in two sections including a first or lower section adjacent the chipper disc and a second or upper section which receives material to be rechipped and in which the guide means are located in the bottom of the upper spout section.

The invention further contemplates a replaceable anvil or stationary cutter operatively associated with the outlet end of each of the spouts for cooperation with the cutter knives carried by the chipper disc.

The chipping installation chown in FIGURE 5 is not to be considered as restrictive of the applicability of the invention. For example, the fan blades could be eliminated from the rear face of the chipper disc, and the stand could be provided with a discharge opening in the bottom. This would permit chipped material to fall by gravity to a level below the chipper. This delivered chipped material could be deposited on a conveyor for transfer to a chip screen and return to the downwardly inclined feed spout. Alternatively, the chipped material could be delivered directly to a chipping installation disposed on a level below the chipping machine and the oversize material from the screening installation could be conveyed by any applicable conveying means back to the downwardly inclined feed spout.

It is to be further pointed out that the location of the two feed spouts is such that the knives carried by the chipper disc are moving downwards across the outlet end of the feed spout 48 and still have a downward impetus when they cross the stationary knife 42.

The invention also contemplates an installation in which the outlet for oversize chipped material from the screening device communicates directly with the inlet end of the downwardly inclined feed spout. Essentially, therefore, the invention comprises a chipping installation including in combination a chipping machine having a knife-carrying chipper disc supported for rotation on a horizontal axis, means for feeding elongated wood pieces horizontally to such chipper disc, 3. chipped material screening device for separating such material into proper size chips and oversized chipped material, means for transferring chipped material from the chipping machine to such screening device, a second feed spout inclined downwardly toward the chipper disc and means for delivering oversized chipped material from the chipping device to such a second spout for rechipping such material.

What is claimed is:

1. A wood chipper comprising the combination of a chipper disc mounted for rotation on a horizontal axis, a housing surrounding said disc, said housing having an outlet for chipped material, a first infeed spout disposed horizontally and communicating with said housing for feeding elongtaed Wood pieces such as logs to the chipper disc, and a second infeed spout having a bottom inclined downwardly toward said housing and having an outlet end communicating with the housing at a level above and at substantially the same radius with respect to said disc as the outlet end of the first infeed spout.

2. A woodchipper as claimed in claim 1, in which said first mentioned spout has one side of its outlet end below and to one side of the axis of said disc and the second spout has its outlet end located on the other side of and above the axis of said disc.

3. A Wood chipper as claimed in claim 2, and guide means on the bottom of said second spout for guiding material to the said disc longitudinally of the axis of such material.

4. A wood chipper as claimed in claim 3, in which said second spout includes a first portion adjacent the housing and a second portion having the inlet end, said guide means comprising ribs of wedge-shaped cross section on the bottom of the second portion of the second spout.

5. A wood chipping installation including in combination a chipping machine having a knife-carrying chipper disc supported for rotation on a horizontal axis, means for feeding elongated wood pieces horizontally to such chipper disc, a chipped material screening device for separating such material into proper size chips and oversized chipped material, means for transferring chipped material from the chipping machine to such screening device, a second feed spout inclined downwardly toward the chipper disc and means for delivering oversized chipped material from the chipping device to such second spout for rechipping such material.

6. A wood chipper comprising the combination of a chipper disc mounted for rotation on a horizontal axis, a housing surrounding said disc, a first infeed spout disposed horizontally and having one side of its outlet end below and to one side of the axis of said disc and adapted to feed elongated wood pieces to said disc, a second infeed spout means having a bottom inclined downwardly toward said housing and having an outlet end communicating with the housing above and at substantially the same radius with respect to said disc as the outlet end of said first spout and on the other side of the axis of said disc, said second infeed spout means including a first portion adjacent the housing and a second portion mounted for axial movement relative to the first portion, and said second portion having ribs on the bottom thereof adapted to insure guidance of short lengths of Wood to the disc longitudinally of the axis of such short lengths.

References Cited in the file of this patent UNITED STATES PATENTS 950,011 Stewart Feb. 22, 1910 1,057,151 Howard Mar. 25, 1913 1,464,690 Andrews Aug. 14, 1923 2,522,904 Evans Sept. 12, 1950 2,554,450 Ayers May 22, 1951 2,596,015 Dunwody May 6, 1952 2,712,903 Dettmering et al July 12, 1955 2,712,904 Durkee July 12, 1955 2,838,248 Ringman June 10, 1958 2,922,586 Hardinge Jan. 26, 1960 FOREIGN PATENTS 73,178 Norway Mar. 1, 1948 

